Compositor API: Add xdg-decoration unstable v1 support

And add an example with server-side window decorations.

Task-number: QTBUG-69934
Change-Id: Ic3984b50cf7574cae5135dea51eb4b1c80bb45a7
Reviewed-by: Paul Olav Tvete <paul.tvete@qt.io>

16 files changed, 614 insertions, 1 deletions

diff --git a/examples/wayland/server-side-decoration/doc/src/server-side-decoration.qdoc b/examples/wayland/server-side-decoration/doc/src/server-side-decoration.qdoc
new file mode 100644
index 000000000..7032152d1
--- /dev/null
+++ b/examples/wayland/server-side-decoration/doc/src/server-side-decoration.qdoc
@@ -0,0 +1,36 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:FDL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Free Documentation License Usage
+** Alternatively, this file may be used under the terms of the GNU Free
+** Documentation License version 1.3 as published by the Free Software
+** Foundation and appearing in the file included in the packaging of
+** this file. Please review the following information to ensure
+** the GNU Free Documentation License version 1.3 requirements
+** will be met: https://www.gnu.org/licenses/fdl-1.3.html.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*!
+ * \title Qt Wayland Compositor Examples - Sever Side Decoration Compositor
+ * \example server-side-decoration
+ * \brief Server Side Decoration Compositor is a simple example that demonstrates server side window decorations on xdg-shell.
+ * \ingroup qtwaylandcompositor-examples
+ *
+ * Server Side Decoration Compositor is a desktop-style Wayland compositor example implementing
+ * server-side window decorations.
+ */
diff --git a/examples/wayland/server-side-decoration/main.cpp b/examples/wayland/server-side-decoration/main.cpp
new file mode 100644
index 000000000..e765fafb6
--- /dev/null
+++ b/examples/wayland/server-side-decoration/main.cpp
@@ -0,0 +1,68 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, you may use this file under the terms of the BSD license
+** as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of The Qt Company Ltd nor the names of its
+**     contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtCore/QUrl>
+#include <QtCore/QDebug>
+
+#include <QtGui/QGuiApplication>
+
+#include <QtQml/QQmlApplicationEngine>
+
+int main(int argc, char *argv[])
+{
+    // ShareOpenGLContexts is needed for using the threaded renderer
+    // on Nvidia EGLStreams
+    QCoreApplication::setAttribute(Qt::AA_ShareOpenGLContexts, true);
+    QGuiApplication app(argc, argv);
+
+    QQmlApplicationEngine appEngine(QUrl("qrc:///main.qml"));
+
+    return app.exec();
+}
diff --git a/examples/wayland/server-side-decoration/main.qml b/examples/wayland/server-side-decoration/main.qml
new file mode 100644
index 000000000..8ec50dd57
--- /dev/null
+++ b/examples/wayland/server-side-decoration/main.qml
@@ -0,0 +1,103 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, you may use this file under the terms of the BSD license
+** as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of The Qt Company Ltd nor the names of its
+**     contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+import QtQuick 2.6
+import QtQuick.Window 2.2
+import QtQuick.Layouts 1.3
+import QtWayland.Compositor 1.3
+
+WaylandCompositor {
+    // The output defines the screen.
+    WaylandOutput {
+        sizeFollowsWindow: true
+        window: Window {
+            width: 1024
+            height: 768
+            visible: true
+            Repeater {
+                model: shellSurfaces
+                Column {
+                    Rectangle {
+                        visible: modelData.toplevel.decorationMode === XdgToplevel.ServerSideDecoration
+                        width: parent.width
+                        height: 30
+                        gradient: "HeavyRain";
+                        RowLayout {
+                            anchors.fill: parent
+                            Text {
+                                text: modelData.toplevel.title
+                                Layout.fillWidth: true
+                            }
+                            MouseArea {
+                                width: 30
+                                height: 30
+                                Text { text: "X"; anchors.centerIn: parent }
+                                onClicked: modelData.toplevel.sendClose()
+                            }
+                        }
+                    }
+                    ShellSurfaceItem {
+                        moveItem: parent
+                        autoCreatePopupItems: true
+                        shellSurface: modelData
+                        onSurfaceDestroyed: shellSurfaces.remove(index)
+                    }
+                }
+            }
+        }
+    }
+    XdgShell {
+        onToplevelCreated: shellSurfaces.append({shellSurface: xdgSurface});
+    }
+    XdgDecorationManagerV1 {
+        preferredMode: XdgToplevel.ServerSideDecoration
+    }
+    ListModel { id: shellSurfaces }
+}
diff --git a/examples/wayland/server-side-decoration/server-side-decoration.pro b/examples/wayland/server-side-decoration/server-side-decoration.pro
new file mode 100644
index 000000000..e6a5cd20a
--- /dev/null
+++ b/examples/wayland/server-side-decoration/server-side-decoration.pro
@@ -0,0 +1,14 @@
+QT += gui qml
+
+SOURCES += \
+    main.cpp
+
+OTHER_FILES = \
+    main.qml
+
+RESOURCES += server-side-decoration.qrc
+
+target.path = $$[QT_INSTALL_EXAMPLES]/wayland/server-side-decoration
+sources.files = $$SOURCES $$HEADERS $$RESOURCES $$FORMS server-side-decoration.pro
+sources.path = $$[QT_INSTALL_EXAMPLES]/wayland/server-side-decoration
+INSTALLS += target sources
diff --git a/examples/wayland/server-side-decoration/server-side-decoration.qrc b/examples/wayland/server-side-decoration/server-side-decoration.qrc
new file mode 100644
index 000000000..5f6483ac3
--- /dev/null
+++ b/examples/wayland/server-side-decoration/server-side-decoration.qrc
@@ -0,0 +1,5 @@
+<RCC>
+    <qresource prefix="/">
+        <file>main.qml</file>
+    </qresource>
+</RCC>
diff --git a/examples/wayland/wayland.pro b/examples/wayland/wayland.pro
index 0cb050cca..b9e4263e7 100644
--- a/examples/wayland/wayland.pro
+++ b/examples/wayland/wayland.pro
@@ -14,6 +14,7 @@ qtHaveModule(quick) {
     SUBDIRS += multi-screen
     SUBDIRS += overview-compositor
     SUBDIRS += ivi-compositor
+    SUBDIRS += server-side-decoration
     qtHaveModule(waylandclient) {
         SUBDIRS += \
             custom-extension \
diff --git a/src/3rdparty/protocol/qt_attribution.json b/src/3rdparty/protocol/qt_attribution.json
index bf5851f84..84dafe938 100644
--- a/src/3rdparty/protocol/qt_attribution.json
+++ b/src/3rdparty/protocol/qt_attribution.json
@@ -40,7 +40,7 @@ Copyright (c) 2013 BMW Car IT GmbH"
         "Id": "wayland-xdg-decoration-protocol",
         "Name": "Wayland xdg-decoration Protocol",
         "QDocModule": "qtwaylandcompositor",
-        "QtUsage": "Used in the Qt Wayland platform plugin.",
+        "QtUsage": "Used in the Qt Wayland Compositor API, and the Qt Wayland platform plugin.",
         "Files": "xdg-decoration-unstable-v1.xml",
 
         "Description": "The xdg-decoration protocol allows a compositor to announce support for server-side decorations.",
diff --git a/src/compositor/extensions/extensions.pri b/src/compositor/extensions/extensions.pri
index b2c55635a..5c708f891 100644
--- a/src/compositor/extensions/extensions.pri
+++ b/src/compositor/extensions/extensions.pri
@@ -11,6 +11,7 @@ WAYLANDSERVERSOURCES += \
     ../3rdparty/protocol/text-input-unstable-v2.xml \
     ../3rdparty/protocol/xdg-shell-unstable-v6.xml \
     ../3rdparty/protocol/xdg-shell.xml \
+    ../3rdparty/protocol/xdg-decoration-unstable-v1.xml \
     ../3rdparty/protocol/ivi-application.xml \
 
 HEADERS += \
@@ -32,6 +33,8 @@ HEADERS += \
     extensions/qwaylandxdgshellv6_p.h \
     extensions/qwaylandxdgshell.h \
     extensions/qwaylandxdgshell_p.h \
+    extensions/qwaylandxdgdecorationv1.h \
+    extensions/qwaylandxdgdecorationv1_p.h \
     extensions/qwaylandshellsurface.h \
     extensions/qwaylandiviapplication.h \
     extensions/qwaylandiviapplication_p.h \
@@ -49,6 +52,7 @@ SOURCES += \
     extensions/qwaylandxdgshellv5.cpp \
     extensions/qwaylandxdgshellv6.cpp \
     extensions/qwaylandxdgshell.cpp \
+    extensions/qwaylandxdgdecorationv1.cpp \
     extensions/qwaylandshellsurface.cpp \
     extensions/qwaylandiviapplication.cpp \
     extensions/qwaylandivisurface.cpp \
diff --git a/src/compositor/extensions/qwaylandxdgdecorationv1.cpp b/src/compositor/extensions/qwaylandxdgdecorationv1.cpp
new file mode 100644
index 000000000..a44d5c19d
--- /dev/null
+++ b/src/compositor/extensions/qwaylandxdgdecorationv1.cpp
@@ -0,0 +1,180 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the QtWaylandCompositor module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL3$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPLv3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or later as published by the Free
+** Software Foundation and appearing in the file LICENSE.GPL included in
+** the packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 2.0 requirements will be
+** met: http://www.gnu.org/licenses/gpl-2.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qwaylandxdgdecorationv1_p.h"
+
+#include <QtWaylandCompositor/QWaylandXdgToplevel>
+#include <QtWaylandCompositor/private/qwaylandxdgshell_p.h>
+
+#include <QtWaylandCompositor/QWaylandCompositor>
+#include <QtCore/QObject>
+
+QT_BEGIN_NAMESPACE
+
+QWaylandXdgDecorationManagerV1::QWaylandXdgDecorationManagerV1()
+    : QWaylandCompositorExtensionTemplate<QWaylandXdgDecorationManagerV1>(*new QWaylandXdgDecorationManagerV1Private)
+{
+}
+
+void QWaylandXdgDecorationManagerV1::initialize()
+{
+    Q_D(QWaylandXdgDecorationManagerV1);
+
+    QWaylandCompositorExtensionTemplate::initialize();
+    QWaylandCompositor *compositor = static_cast<QWaylandCompositor *>(extensionContainer());
+    if (!compositor) {
+        qWarning() << "Failed to find QWaylandCompositor when initializing QWaylandXdgDecorationV1";
+        return;
+    }
+    d->init(compositor->display(), 1);
+}
+
+QWaylandXdgToplevel::DecorationMode QWaylandXdgDecorationManagerV1::preferredMode() const
+{
+    Q_D(const QWaylandXdgDecorationManagerV1);
+    return d->m_defaultMode;
+}
+
+void QWaylandXdgDecorationManagerV1::setPreferredMode(QWaylandXdgToplevel::DecorationMode defaultMode)
+{
+    Q_D(QWaylandXdgDecorationManagerV1);
+    if (d->m_defaultMode == defaultMode)
+        return;
+
+    d->m_defaultMode = defaultMode;
+    emit defaultModeChanged();
+}
+
+const wl_interface *QWaylandXdgDecorationManagerV1::interface()
+{
+    return QWaylandXdgDecorationManagerV1Private::interface();
+}
+
+void QWaylandXdgDecorationManagerV1Private::zxdg_decoration_manager_v1_get_toplevel_decoration(
+        Resource *resource, uint id, wl_resource *toplevelResource)
+{
+    Q_Q(QWaylandXdgDecorationManagerV1);
+
+    auto *toplevel = QWaylandXdgToplevel::fromResource(toplevelResource);
+    if (!toplevel) {
+        qWarning() << "Couldn't find toplevel for decoration";
+        return;
+    }
+
+    //TODO: verify that the xdg surface is unconfigured, and post protocol error/warning
+
+    auto *toplevelPrivate = QWaylandXdgToplevelPrivate::get(toplevel);
+
+    if (toplevelPrivate->m_decoration) {
+        qWarning() << "zxdg_decoration_manager_v1.get_toplevel_decoration:"
+                   << toplevel << "already has a decoration object, ignoring";
+        //TODO: protocol error as well?
+        return;
+    }
+
+    new QWaylandXdgToplevelDecorationV1(toplevel, q, resource->client(), id);
+}
+
+QWaylandXdgToplevelDecorationV1::QWaylandXdgToplevelDecorationV1(QWaylandXdgToplevel *toplevel,
+                                                                 QWaylandXdgDecorationManagerV1 *manager,
+                                                                 wl_client *client, int id)
+    : QtWaylandServer::zxdg_toplevel_decoration_v1(client, id, /*version*/ 1)
+    , m_toplevel(toplevel)
+    , m_manager(manager)
+{
+    Q_ASSERT(toplevel);
+    auto *toplevelPrivate = QWaylandXdgToplevelPrivate::get(toplevel);
+    Q_ASSERT(!toplevelPrivate->m_decoration);
+    toplevelPrivate->m_decoration.reset(this);
+    sendConfigure(manager->preferredMode());
+}
+
+void QWaylandXdgToplevelDecorationV1::sendConfigure(QWaylandXdgToplevelDecorationV1::DecorationMode mode)
+{
+    if (configuredMode() == mode)
+        return;
+
+    switch (mode) {
+    case DecorationMode::ClientSideDecoration:
+        send_configure(mode_client_side);
+        break;
+    case DecorationMode::ServerSideDecoration:
+        send_configure(mode_server_side);
+        break;
+    default:
+        qWarning() << "Illegal mode in QWaylandXdgToplevelDecorationV1::sendConfigure" << mode;
+        break;
+    }
+
+    m_configuredMode = mode;
+    emit m_toplevel->decorationModeChanged();
+}
+
+void QWaylandXdgToplevelDecorationV1::zxdg_toplevel_decoration_v1_destroy_resource(Resource *resource)
+{
+    Q_UNUSED(resource);
+    auto *toplevelPrivate = QWaylandXdgToplevelPrivate::get(m_toplevel);
+    toplevelPrivate->m_decoration.reset();
+}
+
+void QWaylandXdgToplevelDecorationV1::zxdg_toplevel_decoration_v1_destroy(Resource *resource)
+{
+    wl_resource_destroy(resource->handle);
+}
+
+void QWaylandXdgToplevelDecorationV1::zxdg_toplevel_decoration_v1_set_mode(Resource *resource, uint32_t mode)
+{
+    m_clientPreferredMode = DecorationMode(mode);
+    handleClientPreferredModeChanged();
+}
+
+void QWaylandXdgToplevelDecorationV1::zxdg_toplevel_decoration_v1_unset_mode(Resource *resource)
+{
+    m_clientPreferredMode = DecorationMode::DefaultDecorationMode;
+    handleClientPreferredModeChanged();
+}
+
+void QWaylandXdgToplevelDecorationV1::handleClientPreferredModeChanged()
+{
+    if (m_clientPreferredMode != m_configuredMode) {
+        if (m_clientPreferredMode == DecorationMode::DefaultDecorationMode)
+            sendConfigure(m_manager->preferredMode());
+        else
+            sendConfigure(m_clientPreferredMode);
+    }
+}
+
+QT_END_NAMESPACE
diff --git a/src/compositor/extensions/qwaylandxdgdecorationv1.h b/src/compositor/extensions/qwaylandxdgdecorationv1.h
new file mode 100644
index 000000000..649f3d162
--- /dev/null
+++ b/src/compositor/extensions/qwaylandxdgdecorationv1.h
@@ -0,0 +1,69 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the QtWaylandCompositor module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL3$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPLv3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or later as published by the Free
+** Software Foundation and appearing in the file LICENSE.GPL included in
+** the packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 2.0 requirements will be
+** met: http://www.gnu.org/licenses/gpl-2.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QWAYLANDXDGDECORATIONV1_H
+#define QWAYLANDXDGDECORATIONV1_H
+
+#include <QtWaylandCompositor/QWaylandCompositorExtension>
+#include <QtWaylandCompositor/QWaylandXdgToplevel>
+
+QT_BEGIN_NAMESPACE
+
+class QWaylandXdgDecorationManagerV1Private;
+
+class Q_WAYLAND_COMPOSITOR_EXPORT QWaylandXdgDecorationManagerV1 : public QWaylandCompositorExtensionTemplate<QWaylandXdgDecorationManagerV1>
+{
+    Q_OBJECT
+    Q_DECLARE_PRIVATE(QWaylandXdgDecorationManagerV1)
+    Q_PROPERTY(QWaylandXdgToplevel::DecorationMode preferredMode READ preferredMode WRITE setPreferredMode NOTIFY defaultModeChanged)
+
+public:
+    explicit QWaylandXdgDecorationManagerV1();
+
+    void initialize() override;
+
+    QWaylandXdgToplevel::DecorationMode preferredMode() const;
+    void setPreferredMode(QWaylandXdgToplevel::DecorationMode preferredMode);
+
+    static const struct wl_interface *interface();
+
+Q_SIGNALS:
+    void defaultModeChanged();
+};
+
+QT_END_NAMESPACE
+
+#endif // QWAYLANDXDGDECORATIONV1_H
diff --git a/src/compositor/extensions/qwaylandxdgdecorationv1_p.h b/src/compositor/extensions/qwaylandxdgdecorationv1_p.h
new file mode 100644
index 000000000..c09cbc12e
--- /dev/null
+++ b/src/compositor/extensions/qwaylandxdgdecorationv1_p.h
@@ -0,0 +1,107 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the QtWaylandCompositor module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL3$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPLv3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or later as published by the Free
+** Software Foundation and appearing in the file LICENSE.GPL included in
+** the packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 2.0 requirements will be
+** met: http://www.gnu.org/licenses/gpl-2.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QWAYLANDXDGDECORATIONV1_P_H
+#define QWAYLANDXDGDECORATIONV1_P_H
+
+#include "qwaylandxdgdecorationv1.h"
+
+#include <QtWaylandCompositor/private/qwaylandcompositorextension_p.h>
+#include <QtWaylandCompositor/private/qwayland-server-xdg-decoration-unstable-v1.h>
+
+#include <QtWaylandCompositor/QWaylandXdgToplevel>
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+QT_BEGIN_NAMESPACE
+
+class QWaylandXdgToplevel;
+
+class Q_WAYLAND_COMPOSITOR_EXPORT QWaylandXdgDecorationManagerV1Private
+        : public QWaylandCompositorExtensionPrivate
+        , public QtWaylandServer::zxdg_decoration_manager_v1
+{
+    Q_DECLARE_PUBLIC(QWaylandXdgDecorationManagerV1)
+public:
+    using DecorationMode = QWaylandXdgToplevel::DecorationMode;
+    explicit QWaylandXdgDecorationManagerV1Private() {}
+
+protected:
+    void zxdg_decoration_manager_v1_get_toplevel_decoration(Resource *resource, uint id, ::wl_resource *toplevelResource) override;
+
+private:
+    DecorationMode m_defaultMode = DecorationMode::ClientSideDecoration;
+};
+
+class Q_WAYLAND_COMPOSITOR_EXPORT QWaylandXdgToplevelDecorationV1
+        : public QtWaylandServer::zxdg_toplevel_decoration_v1
+{
+public:
+    using DecorationMode = QWaylandXdgToplevel::DecorationMode;
+    explicit QWaylandXdgToplevelDecorationV1(QWaylandXdgToplevel *toplevel,
+                                             QWaylandXdgDecorationManagerV1 *manager,
+                                             wl_client *client, int id);
+
+    DecorationMode configuredMode() const { return m_configuredMode; }
+    void sendConfigure(DecorationMode mode);
+
+protected:
+    void zxdg_toplevel_decoration_v1_destroy_resource(Resource *resource) override;
+    void zxdg_toplevel_decoration_v1_destroy(Resource *resource) override;
+    void zxdg_toplevel_decoration_v1_set_mode(Resource *resource, uint32_t mode) override;
+    void zxdg_toplevel_decoration_v1_unset_mode(Resource *resource) override;
+
+private:
+    void handleClientPreferredModeChanged();
+
+    QWaylandXdgToplevel *m_toplevel = nullptr;
+    QWaylandXdgDecorationManagerV1 *m_manager = nullptr;
+    DecorationMode m_configuredMode = DecorationMode::DefaultDecorationMode;
+    DecorationMode m_clientPreferredMode = DecorationMode::DefaultDecorationMode;
+};
+
+QT_END_NAMESPACE
+
+#endif // QWAYLANDXDGDECORATIONV1_P_H
diff --git a/src/compositor/extensions/qwaylandxdgshell.cpp b/src/compositor/extensions/qwaylandxdgshell.cpp
index 01543135a..205269a88 100644
--- a/src/compositor/extensions/qwaylandxdgshell.cpp
+++ b/src/compositor/extensions/qwaylandxdgshell.cpp
@@ -904,6 +904,12 @@ bool QWaylandXdgToplevel::activated() const
     return d->m_lastAckedConfigure.states.contains(QWaylandXdgToplevel::State::ActivatedState);
 }
 
+QWaylandXdgToplevel::DecorationMode QWaylandXdgToplevel::decorationMode() const
+{
+    Q_D(const QWaylandXdgToplevel);
+    return d->m_decoration ? d->m_decoration->configuredMode() : DecorationMode::ClientSideDecoration;
+}
+
 /*!
  * \qmlmethod size QtWaylandCompositor::XdgToplevel::sizeForResize(size size, point delta, uint edges)
  *
diff --git a/src/compositor/extensions/qwaylandxdgshell.h b/src/compositor/extensions/qwaylandxdgshell.h
index 5467290f6..bcc316e85 100644
--- a/src/compositor/extensions/qwaylandxdgshell.h
+++ b/src/compositor/extensions/qwaylandxdgshell.h
@@ -150,6 +150,7 @@ class Q_WAYLAND_COMPOSITOR_EXPORT QWaylandXdgToplevel : public QObject
     Q_PROPERTY(bool fullscreen READ fullscreen NOTIFY fullscreenChanged)
     Q_PROPERTY(bool resizing READ resizing NOTIFY resizingChanged)
     Q_PROPERTY(bool activated READ activated NOTIFY activatedChanged)
+    Q_PROPERTY(enum DecorationMode decorationMode READ decorationMode NOTIFY decorationModeChanged)
 public:
     enum State : uint {
         MaximizedState  = 1,
@@ -159,6 +160,13 @@ public:
     };
     Q_ENUM(State)
 
+    enum DecorationMode {
+        DefaultDecorationMode,
+        ClientSideDecoration,
+        ServerSideDecoration,
+    };
+    Q_ENUM(DecorationMode)
+
     QWaylandXdgToplevel(QWaylandXdgSurface *xdgSurface, QWaylandResource &resource);
 
     QWaylandXdgToplevel *parentToplevel() const;
@@ -172,6 +180,7 @@ public:
     bool fullscreen() const;
     bool resizing() const;
     bool activated() const;
+    DecorationMode decorationMode() const;
 
     Q_INVOKABLE QSize sizeForResize(const QSizeF &size, const QPointF &delta, Qt::Edges edges) const;
     uint sendConfigure(const QSize &size, const QVector<State> &states);
@@ -206,6 +215,8 @@ Q_SIGNALS:
     void unsetFullscreen();
     void setMinimized();
 
+    void decorationModeChanged();
+
 private:
     QList<int> statesAsInts() const;
 };
diff --git a/src/compositor/extensions/qwaylandxdgshell_p.h b/src/compositor/extensions/qwaylandxdgshell_p.h
index 04d360ee7..70def5f7a 100644
--- a/src/compositor/extensions/qwaylandxdgshell_p.h
+++ b/src/compositor/extensions/qwaylandxdgshell_p.h
@@ -42,6 +42,8 @@
 
 #include <QtWaylandCompositor/QWaylandXdgShell>
 
+#include <QtWaylandCompositor/private/qwaylandxdgdecorationv1_p.h>
+
 #include <QtCore/QSet>
 
 //
@@ -176,6 +178,7 @@ public:
     QString m_appId;
     QSize m_maxSize;
     QSize m_minSize;
+    QScopedPointer<QWaylandXdgToplevelDecorationV1> m_decoration;
 
     static QWaylandSurfaceRole s_role;
 };
diff --git a/src/imports/compositor/qwaylandquickcompositorplugin.cpp b/src/imports/compositor/qwaylandquickcompositorplugin.cpp
index ef2b5203e..f4e727893 100644
--- a/src/imports/compositor/qwaylandquickcompositorplugin.cpp
+++ b/src/imports/compositor/qwaylandquickcompositorplugin.cpp
@@ -64,6 +64,7 @@
 #include <QtWaylandCompositor/QWaylandXdgShellV5>
 #include <QtWaylandCompositor/QWaylandXdgShellV6>
 #include <QtWaylandCompositor/QWaylandXdgShell>
+#include <QtWaylandCompositor/QWaylandXdgDecorationManagerV1>
 #include <QtWaylandCompositor/QWaylandIviApplication>
 #include <QtWaylandCompositor/QWaylandIviSurface>
 
@@ -88,6 +89,7 @@ Q_COMPOSITOR_DECLARE_QUICK_EXTENSION_CLASS(QWaylandXdgShellV6)
 Q_COMPOSITOR_DECLARE_QUICK_PARENT_CLASS(QWaylandXdgSurfaceV6)
 Q_COMPOSITOR_DECLARE_QUICK_EXTENSION_CLASS(QWaylandXdgShell)
 Q_COMPOSITOR_DECLARE_QUICK_PARENT_CLASS(QWaylandXdgSurface)
+Q_COMPOSITOR_DECLARE_QUICK_EXTENSION_CLASS(QWaylandXdgDecorationManagerV1)
 Q_COMPOSITOR_DECLARE_QUICK_EXTENSION_CLASS(QWaylandTextInputManager)
 
 class QmlUrlResolver
@@ -178,6 +180,8 @@ public:
         qmlRegisterType<QWaylandXdgSurfaceQuickParent>(uri, 1, 3, "XdgSurface");
         qmlRegisterUncreatableType<QWaylandXdgToplevel>(uri, 1, 3, "XdgToplevel", QObject::tr("Cannot create instance of XdgShellToplevel"));
         qmlRegisterUncreatableType<QWaylandXdgPopup>(uri, 1, 3, "XdgPopup", QObject::tr("Cannot create instance of XdgShellPopup"));
+
+        qmlRegisterType<QWaylandXdgDecorationManagerV1QuickExtension>(uri, 1, 3, "XdgDecorationManagerV1");
     }
 };
 //![class decl]
diff --git a/sync.profile b/sync.profile
index 40a38745f..756674cda 100644
--- a/sync.profile
+++ b/sync.profile
@@ -61,6 +61,7 @@
         "^qwayland-server-server-buffer-extension.h",
         "^qwayland-server-text-input-unstable-v2.h",
         "^qwayland-server-touch-extension.h",
+        "^qwayland-server-xdg-decoration-unstable-v1.h",
         "^qwayland-server-xdg-shell-unstable-v5.h",
         "^qwayland-server-xdg-shell-unstable-v6.h",
         "^qwayland-server-xdg-shell.h",
@@ -72,6 +73,7 @@
         "^wayland-text-input-unstable-v2-server-protocol.h",
         "^wayland-touch-extension-server-protocol.h",
         "^wayland-wayland-server-protocol.h",
+        "^wayland-xdg-decoration-unstable-v1-server-protocol.h",
         "^wayland-xdg-shell-server-protocol.h",
         "^wayland-xdg-shell-unstable-v5-server-protocol.h",
         "^wayland-xdg-shell-unstable-v6-server-protocol.h",